In the related art, in an automobile or the like, in some cases, electric wires are connected by using a connector (hereinafter referred to as “a waterproof connector”.) excellent in a waterproof property. For example, a waterproof connector structure is known which includes a female connector which has a cylindrical inner housing formed with a cavity (terminal receiving chamber) which can receive a female terminal and a cylindrical outer housing which surrounds the inner housing, and a male connector which has a cylindrical housing formed with a cavity (terminal receiving chamber) which can receive a male terminal, wherein both connectors are fitted such that the housing of the male connector is inserted into a gap between the inner housing and the outer housing of the female connector.
An annular rubber packing is mounted on the outer circumferential surface of the inner housing of the female connector, and when both connectors are fitted, the housing of the male connector is inserted into the gap of the female connector. Further, the packing is brought into close contact with the outer circumferential surface of the inner housing of the female connector and with the inner circumferential surface of the housing of the male connector, so as to block the gap, and thus, which prevents water from entering the opening of the cavity of both housings.
However, an annular space for mounting the packing in the female connector is required in this waterproof structure, whereby the female connector (and also the waterproof structure) is larger compared to the case of the connector which does not require such a space.
On the other hand, in JP-A-2013-229168, a waterproof structure which does not use the packing is described in which an annular seal plate having an elasticity is provided in the female housing, and a cylinder tip of the male housing is pushed to the seal plate at the time of fitting the female housing and the male housing. Accordingly, entry of the water through between the female housing and the male housing is prevented (for example, see JP-A-2013-229168).